Theory of Machines Tests - Set 12

Practice Test: Question Set - 12

1. The axis of
precession is __________ to the plane in which the axis of spin is going to
rotate.

(A) Parallel

(B) Perpendicular

(C) Both A and B

(D) None of
these

Answer: Option B

2. The ratio of
the maximum displacement of the forced vibration to the deflection due to the
static force, is known as

(A) Damping
factor

(B) Damping
coefficient

(C) Logarithmic
decrement

(D) Magnification
factor

Answer: Option D

3. If the radius of gyration of
a compound pendulum about an axis through e.g. is more, then its frequency of
oscillation will be

(A) Less

(B) More

(C) Same

(D) Data
are insufficient to determine same

Answer: Option A

4. Klein's construction is
useful to determine

(A) Velocity
of various parts

(B) Acceleration of various parts

(C) Displacement
of various parts

(D) Angular acceleration of
various parts

Answer: Option B

5. In the below
figure, PC is the connecting rod and OC is the crank making an
angle θ with the line of stroke PO and rotates with uniform angular
velocity at ω rad/s. The Klien's acceleration diagram for determining the
acceleration of the piston P is shown by quadrilateral CQNO. The
acceleration of the piston P with respect to the crank-pin C is
given by

(A) ω² ×
NO

(B) ω² ×
CO

(C) ω² ×
CN

(D) ω² ×
QN

Answer: Option C

6. When the
crank is at the inner dead center, in a reciprocating steam engine, then the
acceleration of the piston will be

(A) ω²r.
(n + 1)/n

(B) ω²r.
(n - 1)/n

(C) ω²r.
n/(n + 1)

(D) ω²r.
n/(n - 1)

Answer: Option A

7. Under
logarithmic decrement, the amplitude of successive vibrations are

(A) Constant

(B) In
arithmetic progression

(C) In geometric
progression

(D) In
logarithmic progression

Answer: Option C

8. A spring controlled governor is said to be
stable if the controlling force line when produced intersects the Y-axis

(A) At the origin

(B) Below the origin

(C) Above the origin

(D) Any one of these

Answer: Option B

9. Which of the following
disciplines provides study of relative motion between the parts of a machine?

(A) Theory
of machines

(B) Applied
mechanics

(C) Mechanisms

(D) Kinematics

Answer: Option D

10. Cross head and guides form a

(A) Lower pair

(B) Higher
pair

(C) Turning pair

(D) Sliding pair

Answer: Option D

11. In a
coupling rod of a locomotive, each of the four pairs is a ________ pair.

(A) Sliding

(B) Turning

(C) Rolling

(D) Screw

Answer: Option B

12. The two
links OA and OB are connected by a pin joint at O. If the
link OA turns with angular velocity ω₁ rad/s in the clockwise direction
and the link OB turns with angular velocity ω₂ rad/s in the clockwise
direction, then the rubbing velocity at the pin joint O is (where r =
Radius of the pin at O)

(A) ω₁.ω₂.r

(B) (ω₁ - ω₂)r

(C) (ω₁ +
ω₂)r

(D) (ω₁
- ω₂)2r

Answer: Option B

13. The dynamic
friction is the friction experienced by a body, when the body

(A) Is
in motion

(B) Is at rest

(C) Just begins
to slide over the surface of the other body

(D) None of the
above

Answer: Option A

14. The
frictional torque transmitted in a flat pivot bearing with assumption of uniform
pressure is _________ as compared to uniform wear.

(A) Less

(B) More

(C) Same

(D) None of
these

Answer: Option B

15. A foot step bearing and rotor
of a vertical turbine form examples of